1. Technical Field
This invention deals generally with monitoring and displaying aircraft operational parameters, especially those associated with an aircraft engine. A display of similar general type is available as a Graphic Engine Monitor (GEM®—registered trademark of Insight Avionics, Inc.) and typically comprises a main unit located on the aircraft cockpit panel for display of real-time and/or historical information concerning the aircraft and/or engine. More generally applicable fuel tank monitoring, thermocouple resistance measuring techniques and vibration/balance analysis techniques are also addressed hereinbelow.
2. Related Art
Aircraft monitoring instruments have been available for many years from a number of manufacturers. In general, prior monitors have included a bar graph for each cylinder of a reciprocating aircraft engine simultaneously showing exhaust gas temperature (EGT) and cylinder head temperature (CHT). Data concerning cooling trends, differential temperatures between cylinders, fuel flow (FF), RPM, fuel reserve, total aircraft fuel used and/or remaining, outside air temperature, intake air temperature, percent brake horsepower (HP) being developed by the engine and other aircraft performance parameters have been accumulated and displayed. Typically, the bar graphs may be created by discrete display elements arranged in a linear array bar format for each cylinder (e.g., the overall lighted bar length/height representing EGT and an unlighted element therewithin representing CHT). Digital readouts of other data have been available and historical data storage/readout of such parameters has been provided for downloading to a laptop or other computer and later analysis as will be appreciated by those in the art.
Some prior monitors also provide visual indicators for assisting the pilot in leaning the engine (either rich of peak (ROP) or lean of peak (LOP)) for sustained operation (e.g., after climb-out to altitude).
Some more recent monitors have provided increased resolution display using television-type raster-scanned display screens—but typically of a relatively larger size than is easily fit within the standard available spaces (e.g., a 2¼-inch diameter hole) on an aircraft panel (at least for legacy aircraft retrofit purposes).